Audi Workshop Service and Repair Manuals > A3 Mk1 > Power unit | Simos injection and ignition system (4-cylinder) | Mixture preparation system, electronic inj.,Gas | Checking Lambda control | Checking lambda probe and lambda control downstream of catalytic converter

Test sequence

–	Connect vehicle diagnostic, testing and information system -VAS 5051- or fault reader -V.A.G 1551- and select engine electronics control unit by entering “address word ” 01. For this purpose, the engine must be running at idling speed.

Indicated on display:

–	Enter “04” for the function “Start basic setting” and confirm entry with the Q key.

Note!

During basic setting, the activated charcoal filter solenoid valve (ACF valve -N80-) is closed and the air conditioner compressor is switched off.

Rapid data transfer HELP

Select function XX

Indicated on display:

–	Enter “043” for “Display group number 043” and confirm entry with the Q key.

Initiate basic setting  Q

Enter display group number XXX

Indicated on display:

–	Increase engine speed by accelerating to approx. 3000 rpm until a temperature is displayed in display zone 2 that is clearly above 250 °C. Then remove foot from accelerator, so that engine is running at idling speed.

–	Set engine speed to 2800...3200 rpm using engine speed controller -V.A.G 1788/10-.

–	Actuate the brake pedal and hold down until the display in display zone 4 jumps from “Test OFF” to “Test ON”.

–	Continue to maintain engine speed at 2800...3200 rpm and keep brake pedal pressed until result of diagnosis appears in display zone 4.

System in basic setting 43        ->

         1         2         3         4

	Display zones
	1	2	3	4
Display group 043: Diagnosis of lambda probe ageing, lambda probe downstream of catalytic converter
Display	xxxx rpm	xxx °C	x.x V	---
Readout	Engine speed	Exhaust gas temperature	Lambda probe voltage Bank 1, probe 2	Diagnosis status
Range	0...6500	70...850 °C	0...1.0 V	Test OFF Test ON B1–S2 OK B1–S2 NOK
Specification	2800...3200 rpm	Above 250 °C	0.0...0.95 V	B1-S2 OK
Note:			If the specification is not attainted ⇒ Continued on Page → Chapter

Note!

Calculated value from engine speed and load.

Audi Workshop Service and Repair Manuals